J/A+A/515/A51 Extended red(dened) regions in 2MASS (Frieswijk+, 2010)
Searching for dark clouds in the outer galactic plane.
I. A statistical approach for identifying extended red(dened) regions in 2MASS.
Frieswijk W.W.F., Shipman R.F.
<Astron. Astrophys. 515, A51 (2010)>
=2010A&A...515A..51F 2010A&A...515A..51F
ADC_Keywords: Galactic plane ; Infrared sources ; Molecular clouds
Keywords: method: statistical - catalogs - stars: formation - ISM: clouds -
dust, extinction
Abstract:
The aim of this paper is to identify extended red regions in the outer
galactic plane based on reddening of stars in the near-infrared. We
argue that these regions appear reddened mainly due to extinction
caused by molecular clouds and young stellar objects. The work
presented here is used as a basis for identifying star forming regions
and in particular the very early stages. An accompanying paper
describes the cross-identification of the identified regions with
existing data, uncovering more on the nature of the reddening.
Description:
Basic parameters of 2909 extended red regions in the outer Galactic
plane (1320 at 60" and 1589 at 90" resolution). The sources have been
extracted from the Two Micron All Sky Survey (2MASS, Cat. II/246).
For each source Galactic coordinates, total number of resolution
cells, linear extend in longitude and latitude and number of 2MASS
point sources are given. The calculated reliability of the sources is
>99.9%.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 36 2909 Basic parameters of extended red regions in the
outer Galaxy
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- FrSh Extended red region number, HNNNN or LNNNN (1)
7- 12 F6.2 deg GLON Galactic longitude of red region center
14- 18 F5.2 deg GLAT Galactic latitude of red region center
20- 22 I3 --- Ncell Total number of red cells (2)
24- 26 I3 pix dLon Extent in Galactic longitude (3)
28- 30 I3 pix dLat Extent in Galactic latitude (3)
32- 36 I5 --- 2M Number of 2MASS sources (4)
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Note (1): Lines 1 to 1320 are regions H1 to H1320 extracted at 60"
resolution and are preceded by 'H' for high resolution;
lines 1321 to 2909 are regions L1 to L1589 extracted at 90" resolution
and are preceded by 'L' for low resolution.
Note (2): The number of cells that an extended red region consists of. By
definition this number is larger than 3.
Note (3): For high resolution regions 1 pixel corresponds to 60". For low
resolution regions 1 pixel corresponds to 90".
Note (4): The total number of 2MASS sources that are present in the cells
that make up an extended red region (see Note 2).
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Acknowledgements:
Wilfred Frieswijk, frieswyk(at)astro.rug.nl
(End) W. Frieswijk [Kapteyn Inst., The Netherlands] P. Vannier [CDS] 26-Apr-2010